Fuel feeding means



March 7, 1933. M. KAHR 1,900,385

FUEL FEEDING MEANS Original Fil d March 5, 1926 4 Sheets-Sheet 1 INVENTOR m, mmvm ATTORNEYS March 7, 1933.

M. KAHR FUEL FEEDING MEANS 4 Sheets-Sheet 3 Original Filed March 5, 1926 w M wj w v M Y m m 4 D IW. g 9 M M 2 M 7 2 M m M W H M m X I 1 m 7 8 7 6. H m.

ATTORNEYS March 7, 1933. MQKAHR 1,900,385

" FUEL FEEDING MEANS Original Filed March 5. 1926 4 Sheets-Sheet 4 N I INVENTOR ATTORNEYS Patented Mar. 7, 1933 um'rao STATES PATENT OFFICE MARTIN ana, or FRANKLIN, rnNNsYLvaNn, assreNoa TO rmxu vknvnnnss ENGINE coiurm, or FRANKLIN, PmsYLvANm, a conronn'rroN or PENNSYL- VANIA :ennr. FEEDI G mums Original application filed March :5, 1928, Serial No. 92,573. Divided and this application filed lay 19,

This invention relates to internal combus t1on engines, and whlle certain features of the invention are susceptible of embodiment A vention, to the particular utility of an engine of this type in oilfield service, but it is to be expressly understood that the invention is not restricted to an engine so employed. This application is a division of my application Serial Number 92,573, filed March 5, 1926, for internal combustion engines.

One of the major objections. heretofore raised to Diesel and semi-Diesel engines, and

i and then, when the drill has been raised to.

one that has militated against the more widespread use ofengines of this type, is their rinflexibility' in service. For many services to which internal combustion engines are put it is highly desirable, if not essential, that the engine be 'capabl'eof operating under a wide variety of loads and ofvrunning at a wide variety of speeds. For example, in oil fieldwork an engine employed for drilling a well must be capable of elevating the drill under what'constitutes a full load condition the top of its stroke, the engine must speed up sufficiently so as not to interfere with the down stroke of the drill, sometimes running under what amounts to a no-load condition. As the drill rebounds, the engine must be running at such speed as to pick up the drill promptly on its rebound, and carrydt to the top of its stroke, with the consequent increase in load but without undue diminution of speed. These continually changing con I (litions of load and speed require an engine which is possessed of considerable flexibility. Oil engines as heretofore constructed have not possessed the requisite flexibility for services of this character, and it has been considered necessary to design each engine operating on a Diesel on semi-Diesel cycle to some particular condition of load and speed. It is an object of this invention to provide an 1927,. Serial No. 192,614.

oil enginewhich is highly flexible so that it i at the proper time and underfthe proper pressure accurately regulated quantities of liquid fuel by use of a construction which is relatively simple and inexpensive and yet rugged and effective in operation.

provision of improved means for adjusting the timing of the fuel injection; improved means for throwing the fuel phmp into and out of operation; improved means for preventing undesirable vibrations as a result of the cooperation of the governor mechanism with the fuel pumping and regulating devices; improved means for regulating, the quantity of liquid fuel discharged into the engine cylinder; and improved means for pumping liquid fuel. Other objects will appear as the description of the invention proceeds.

The invention is capable of receiving a variety of mechanical expressions, one of which has been shown on the accompanying drawings, but it is to be expressly understood that the drawings. are for purposes of illustration only, and are not to beconstrued as a definition of the limits of the invention, ref erence being bad to the appended claims for that purpose. 1

Referring in detail to the drawings, wherein the same reference characters are employed to designate corresponding parts in the several figures:

Fig. 1 is an elevation partially in axial section of a fuel pump andregulating and governing mech anism embodying the present invention.

Fig. 2 is an' axial section through the fuel Other objects of the invention relate to the I needle or by-pass valve;

Fig. 8 is an enlarged detailed section through the inlet chamber in the fuel pump taken on line 88 of Fig. 1 and Figs. 9 and 10 are perspective views of the cooperating collars which constitute means for adjusting the timing of the fuel injection.

As pointed out above, the invention ineludes improved fuel pumping and regulating mechanism which is assumed hereinafter to be employed in conjunction with a suitable oil engine of the Diesel or semi-Diesel type provided with suitable fuel injectorsfor injecting liquid fuel into the cylinders of the engine.

In, conformity with the present invention means are employed for delivering li uid T fuelto an injector device embodying a uel pumping and regulating device which avoids the use of compressed air. One embodiment of the invention is illustrated in Figs. 1 to 10 inclusive. Mounted on a suitable base 110 projecting from the frame of the engine is a pump casing 111 whichis provided inte- 116 (Fig. 8) in which is received an inlet nip'' riorly. thereof with an inlet chamber 112, a pump cylinder 113, and a needle or by-pass valve chamber .114. Chamber 112 is pr0vid-;

ed at itsbottom with a threaded aperture ple 117 threaded at its inner end for engage- .ment in said aperture. Said nipple 117 has a, passage 118 extending therethrough which is threaded from its opposite ends as shown at 119 and 120. Threaded into the end 119 of said nipple ,is a supply pipe 121 which leads from anysuitable tank or other source of liquid fuel. Threaded into the end 120 of said nipple 117 is a strainer support 122 provided with an axially extending passage 123 which communicates with the exterior of the support through perforations 124 distributedthroughout substantially the entire, cylinjdrical surface of said support. At its upper -end said. support is provided with an enlarged head 125, slotted at 126, and at its opposite end said support is provided with an enlargement 127 and a threaded end 123 for coaction with-the threads 120. Supported on the strainer support 122 is astrainer .129 which is retained at its upper end by the shoulder afforded by enlarged head 125 of said support, and whichis held at its lower end between enlargement 127 on said support and the wall 130 of an enlarged section of the passage 118. Said strainer may be mounted on the support 122, and the support .then threaded into the nipple 117 by the engagement of a screw driver in the slot 126,

the strainer being clamped between the enproper. Referring to Fig. 8, it will be 'observed that the chamber 112 extends a considerable distance above said port 131 so as to form a dead air space within said chamber. Said dead air space constitutes an elastic cushion which receives the shock of the inflowin column of fuel from the supply line .121. Faaid chamber 112 is also preferably provided with an aperture 132 in its exterior wall above the plane of the port 131, and into this aperture is secured a cock 133 of any suitable construction. When the engine is to be put into operation the cock, 133 is opened so as to permit the liquid fuel to fiow -into the chamber 112 until it reaches the level of said aperture 132, the air that otherwise would erture 132 constitutes a dead air chamber the elasticity of the air within which acts as a 11Sll1lOIl to absorb the shock of the inflowing Chamber 113 which constitutes the cylinden of the pump (see Fig. 2) extends throughout the height of the casing and intermediate its length is enlarged to provide a chamber 134 with which communicates the port 131 heretofore described. At the lower end said chamber 113 is enlarged to receive a packing ring 135 and at its upper end said chamber is enlarged and threaded at 136 to receive the discharge valve nipple 137.

Slidably mounted in said cylindrical chamber 113 is the plunger 140 of the fuel pump. Said lunger is provided with an axially extending passage 141 which communicates at its lower end with one or more radial passages 142 designed to communicate with the chamber 134 in order that the incoming fuel may flow to the passage 141 through the radial passages 142. Passage 141 adjacent itsupper end is enlarged as shown at 143 and then further enlarged and interiorly threaded as shown at 144. Mounted within the enlarged sections 143 and 144 is the inlet valve which, in the form shown (see Fig. 4),

includesQa ball 145 designed to seat against the conical surface 146 which connects the main portion of the passage 141 with the first enlargement 143, and a coil spring 147 which engages said ball 145 and tends to plunger. The nut 149 has an aperture 150 extending therethrough, and is preferably provided with -a slot 151' so that the fuel may reach said aperture 150 even though the ball 145 be raised so far as to cause the coils of the spring 147 tocontact. Said nut may also have a slot 151 so that it may be threaded into position by the engagement of ascrewdriver in said slot. .When threaded into operative position the lower end of said nut- 29 engages the shoulder 152 between the first and second enlargements, 143 and 144 respectively, in the axial passage through the plunger, and in this position said nut may be locked by a spring-locking ring 153, the

wall of the enlargement 144 being desirably formed with a circumferential'groove 154 to receive said spring-locking member.

The nipple 137 of the discharge valve includes an exteriorly threaded portion 155 for reception within the threaded aperture 136 at the top of the pump casing, and above. said threaded portion said nipple is preferably squared or otherwise suitablyformed so that it may be mounted in operative position by the engagement of a wrenchtherewith. Said nipple is. provided with an axially extending passage 156 which adjacent its lower end is reduced in diameter to provide a conical seat 157 for the discharge valve. At its upper end said passage 156 is enlarged and interiorly threaded as shown at 158 to receive the gland sleeve 159 of union or coupling member 160. The discharge valve may be of any suitable constructionbeing shown as of the 5 same construction as the inlet valve and including (see Fig. 3) the ball 161 which is held in engagement with-the seat 157 b a coil spring 162 which reacts between said all-andthe bottom ofra recess in a nut 163 provided with an axial passage 164, said n'ut being locked in operative position by a spring ring 165 with the lower end of said nut 163 in contact with a shoulder 166 formed between the intermediate threaded portion 167 of the pas- 5 sage 156wand the lower adjacent section 168 0 the intermediate threaded portion 167 and the upper threaded portion 158 of passage 156, and said coupling member 160 is held with said conical surfaces 17 0 and 171 in fluid-tight or valve-like contact by the gland nut 159 which engages a shoulder 172 on said coupling member. Similarly the nipple 137 is provided at its inner end with a conical surface 17 3. which makes a fluid-tight contact with a similar conical surface 174 between the enlarged interiorly threaded por- 177 for the normal flow of oil and an aperture 178, at the top of said passage, which communicates with a threaded aperture 17 9. In said threaded aperture 179 is a valve member 180 in the form of a cap screw shaped at its lower end to close said aperture 178. A second aperture 181 leads from the threaded aperture 17 9 to the exterior of the housing 176, so that if valve 180 is backed off to open the apertures 178 and 181 any air which has accumulated in the passage 17 7, which is the highest point'in the line from the fuel pump to the injector device, may escape through said apertures. When the line is full of oil, valve 180 is returned to its seat to prevent the escape of fuel through the aperture 178. Passage 177 communicates through aperture 182 with an angle union 183 which again connects through angle union 184 with the pipe 185 in the discharge line.

In the preferred embodiment of this invention a by-pass valve is provided in the discharge conduit to regulate the amount .of liquid fuel which is delivered to the in'ector by the fuel pump heretofore describe In the form shown, the casing 111 is provided with a by-pass valve chamber 114 as hereto fore referred to, said chamber being formed in a lateral projection 190 of the casing 111 as shown in Fig. 5 Adjacent the bottom of said casing projection 190 there is provided a transverse passage 191 which at one end communicates with pipe 185 through pipe 192 and a union 193 of any suitable construction. At its opposite end said passage communicates through union 194 with pipe 195 leading to the inlet passage of the injector.-

By preference one or more check valves, preferably two, are interposed in this line.

Said passage 191 communicates through a needle opening 196 with a chamber-197' which in turn communicates with the chamber 114 of the needle valve through apertures 198 in a transverse wall 199' which separates said chamber 197 from the chamber 114. Mounted within a central aperture 200 in said partition 199 is a needle valve 201 which carries a collar 202 between which and a second collar 203 loosely mounted on the stem of said needle valve is interposed a coil spring 204. The upper end of chamber 114 is interiorly threaded at 205 and received within said threaded portion is a coupling nut 206 which is recessed throughout the majorportion of its length as shown at 207 to receive the upper end of the coil spring 204, the loose collar 203 and a packing ring 208 which is interposed betwcen said ring 203 and the bottom of said recess 207. The stem of the needle valve.

extends through an aperture 209 in the head of the coupling nut and is threaded at its, upper end for a purpose to behereinafter described. The packing 208 is held in sealingcontact with thebottom ofthe recess 207 and around the-stem of the needle valve by the reaction of the spring 204 on the loose washer 203 so that escape of fuel through the aperture 209 is prevented. Spring 204 also by its coaction with the collar 202 on the needle valve tends to hold the needle valve closed except when the same is opened in the manner hereinafter'described. When open the liquid fuel flowing through the trans-. verse passage 191 from the discharge pipe 185 may flow upwardly through the needle opening 196- into the chamber 114.. From chamber 114 the liquid fuel-is returned to the inlet connections inany suitable way. In the form shown the casin 111 is provided with a cored passage 210 see Fig. 5) which leads fronrthe chamber 114 to the inlet chamber 112, so that any gas formed from the liquid fuel will accumulate in the dead alr spaces in said chamber 112. 0

Pump plunger 140 may be operated in any suitable way. In the formshown, said plunger extends below. the pump casing'lll where it is provided with a collar 215. between which collar and a loose" ring 216 mounted on sald plunger is interposed a coil spring 217. G011 spring 217 byits reaction on ring 216 holds the packing 135 heretofore referred to in sealing contact with the peripheral surface of the plunger so as to prevent leakage of the 011 downwardly around the plunger from the.

chamber 134." 1

It will be noted that the liquid fuel 1n the chamber 134 is at substantially the pressure in the feed line,121; hence there is no h gh pressure on the fuel in chamber 134 tending to cause it to leak downwardly around the plunger, and any tendency to leak that may exist is prevented by the packing 135. Any leakage of fuehdownw'ardly around the up-' per endof the plunger is retl'rned to the chamber 134 which is at the lower pressure, while leakage around the discharge valve nipple or the coupling member 160 leading to the discharge conduit is prevented by the valve-like contact between the cone surfaces heretofore described. Hence leakage of fuel from the pump is efiect'ively but simply prevented. i

modest Collar 215 may be formed integrally with the lower end of plunger 140 or it may be separately formed and secured thereon in any suitable way as by shrinking the same ontothe reduced lower end 218 of said plunger.

Said collar on its under-face is recessed as shown at 219 to receive and retain a disk 220 of fiber or any other suitable materialffor receiving the impact of the plunger operating device.

Said plunger operating devicesmay be of any suitable construction. Inthe form shown a plunger lifter 221 is mounted for reciprocating movement within an aperture 222 provided in a transverse wall or web of the'bracket 110. Said lifter at itsupper end is recessed as shown at 225' to receive a contact pin or plunger 224 which is normally pressed upwardly into contact with disk 220 by coil spring 223 reacting between said. plunger pin and the bottom of said recess 225. I Lifter 221 is slotted intermediate its length as shown at 226 and bifurcated at its lower end shown at 227 (Fig.1). In the furcations of said bifurcated portion. 227 is mounted a roller 228 on a roller pin 229 retained in apertures in said furcations in any suitable way, as by set screws 230.

The upper end wall of slot 226 is provided with a downwardly extending conical pro.- jection 231 and extending through said slot 226 is a lever 232 suitably pivoted on the frame or bracket, as at 233, said lever being designed to liftthe roller 228 from operative contact with its cam 234. Said lever is preferably provided in its upper surface with a notch 235 in position. to coact with the downwardly extending conical projection 23 1, the angularity of a wall of said notch being so selected with respect to the angularity of the surface of the conical projection 231 that when said notch is engaged with said conical projection, in the'position of the lever where- Y in the roller 228 is held ofi of its cam 234, the parts are locked in that position owing to the friction between the wall of the notch 235 and the surface of'the conical projection 231.

The lever may be readily lowered to return the roller228 t5 the surface of its cam 234 by exerting sufiicient pressure on said lever to overcome the friction between the wall of the notch 235 and the conical projection 231.

Iiifter 221 is reduced in diameter intermediate its length as shown at 240 and mounted on said portion 240 in any suitable way, as by shrinking the same thereon,is a laterally projecting arm 241 for operating the mechanism to control the needle valve. Said mechanism includes an upwardly extending lifter rod 242 which at its lower end projects into a position where it may be engaged by the lifter arm 241. Said rod extends upwardly through a guide aperture 243 in a lug 244 on the pump casing, and at its upper end is provided with a collar 245 held thereon in any suit-able way, as by transverse pin 246 positioned in an aperture in the rod 242. A. coil spring 247 is interposed between said collar 245 and the lug 244 whereby said pin is normally pressed upwardly into engagement 252. Also mounted on said stem' 250 is a regulating lever 253 provided with a slot 254 through which said stem 250 extends, said stem being flattened on either side for reception in said slot. Said lever 253 on either side of said slot is provided on its upper face with a fulcrum surface 255 for engagement with the lower face of the nut 251. Said'lever at its end 256 extends into a position Where it is engaged by the upper end of the lifter rod 242 (see Fig. 1). At its opposite end 257. said lever is pivoted at 258 to a movable element the position of which is controlled by governor mechanism.

Lever 253 is therefore a floating lever which is actuated by lifter rod 242, engaging its end 256, each time the pump plunger is elevated, because each time the pump plunger is raised the contact arm 241 engages and lifts the rod 242, and the upper end of saidfrod is always held by the spring 247 in contact with the end 256 of said lever. The elevation of end 256 of lever 253 causes the needle valve stem to be lifted by the engagement of the son of the upward pressure of the spring 247 on rod 242 in engagement with said end 256 of the lever. Hence the lower end of rod 242 is elevated with respect to contact arm 241 and the latter will engage said pin 242 to lift the needle valve only adjacent the end of the upward stroke of the plunger. If fulcrum 258 is relatively high, on the other hand, the lever 253 is tilted aboutits fulcrum surface 255 so as to depress end 256 and thereby the lower end of the rod 242 is pressed downwardly into a position where it is engaged with the contact arm 241 at an earlier point in the stroke of the plunger, so that the needle valve is open at an earlier portion of said stroke. Hence the instant at which the needle valve is opened with respect to the length of the stroke of the plunger depends upon the position of the fulcrum 258.

Fulcrum 258 is adjusted by means of governor mechanism of any suitable construction, In the form shown said fulcrum takes the form of ashort shaft or pin which is carried by an L-shaped arm' 260 which projects downwardly into a position to be operated by a governor or control lever 261 suitably pivoted, as at 262, to the housin of the governor. Said governor may be 0 any suitable construction but preferably is of the type disclosed in Letters Patent No. 1,630,637 granted May 31, 1927, to CharlesH. Sheasley and Ed ar H. Crossen. I

Brie y, said governor includes a driven shaft 263 which carries fly-balls 264 mounted on arms 265 pivoted to the governor sleeve 266 which rotates with the shaft 263. Said balls 264 are also connected by links 267 to the vertically movable rod 268 which rotates with a guide sleeve 269.v A ball bearin 270 is interposed between the rotatable e ements of the governor and anon-rotatable vertically movable thrust rod 271 to which the lever 261 is inned by the pivotal connection 272. Threa ed within the upper end of the governor housing 273 is an exteriorly threaded sleeve 274 which at its lower, end is provided with a stop flange 275 and which, intermediateits length, carries a stop collar 276 which may be securedin adjusted'position thereon by means of a set screw 277. The

- upper end of said sleeve 274 carries a pulley 278 retained thereon by a nut 279. Threaded into the sleeve 274 is an adjusting screw 280 between the inner end of which and a shoulder 281'on the thrust rod 271 is interposed a coil spring 282. For oil field service said spring 282 is made relatively stiff for the reasons explained in the application of Sheasley andCrossen heretofore referred to, although for other purposes a lighter and more sensitive spring may be employed if desired. Said coil sprin 282 opposes the outward move ment of t e fly-vballs 27 4 and maybe placed under different degrees of tension by rotatin the threaded sleeve 274 inwardly or outwar ly with respect to the governor housing 273. The stop'flange 275 and the stop collar 276 are provided for determining t e limits of such movement for reasons explained in said application of Sheasley and Crossen, and the adjustment of said sleeve is efl'ectedby' a cord extendingaround pulley 278 in the manner described in said application.

As the speed of the engine increases and the fly-balls 264 fly outwardly the thrust rod 271 is elevated to raise the control lever 261',

and thereby raise the fulcrum pin 258 to effeet the operation of the needle valve and the;

cuttin' off of theinjection of fuel at an earlier peri in the stroke of the pump plunger in the manner heretofore described. As the engine decreases in speed, the fiy-balls move inwardly, the lever 261 is lowered, as is also the fulcrum pin 258, and the needle valve is operated at a later period during'the stroke of the pump plun er as heretofore described.

Therefore, theapstant at which the needle where it is provided with a flange 290. Secvalve is operated to out ed the injection of :the degree of sensitlveness coil spring 282.

fuel is nicely and accurately regulated'in conformity with the speed of-the engine within determined by the In order to prevent undue oscillation of the fulcrum 258 under the influence of the actuation of the lever 253 by the lifter rod 242, means are preferably provided for dampenin'g the movements of said fulcrum 258. If

pivot pin 258 and the connection therefrom to the control lever 261 are sufficiently long so that the side thrust on these elements produces such friction as to retard relative movements, separate means for dampening the movements of the fulcrum 258 are unnecessary. But I preferably connect said fulcrum 258 with the piston of a dash pot. In the form shown, the governor housing is provided at 282 with a cylinder, and mounted within said cylinder is a piston 283 having suitably restricted apertures and an upstanding post 284 on which fulcrum pin 258 is mounted. When a dash pot is thus provided the fulcrum 258 will be moved through the L-shaped gearing 286 is interposed between said layshaft and the governor spindle 263. Said wa and said flan #5 lay-shaft 285 also carries the pump plunger operating earn 234 which cooperates with the roller 228 on plunger lifter 221, as heretof ore described, said cam operating to time the actuation of the pump plunger, and therefore the injection of .the fuel into the combustion chamber, at the proper instant in the stroke of the piston. In order to provide for ad'ustment in this timing of the actuation o the pump plunger, said cam 234 is mounted on a sleeve 288 which extends outside of the oil ti ht crank casing 289 tion 291 of the lay-shaft is also provided with a flange 292 secured thereon in any suitable loc ed together in dlfierent positions of circumferential adjustment to vary the time of actuation of the pump plunger-with respect to the stroke of the piston. .To this end, said flanges. 290 and 292 are rovided with circumferential apertures an as shown in Figs.

9 and 10, the number of said apertures in the two flanges is unequal. .Any desired number of apertures may be provided depending on the nicety or fineness with which it is desired to make the adjustment. In the s are desi nod to be form shown the flange 290 is provided with thirteen apertures 293 and the flange 292 is provided with twelve apertures 294. The flanges are locked together by a bolt 295 which passes through one of the apertures in flange 292 and is threaded into one of the apertures in flange 290. By withdrawing so that there is no opportunity for slippage between the parts, as frequently occurs where the adjustment of the cam is effected by parts which are retained in adjusted position by friction.

In operation the amount 'of fuel injected into'ithe combustion chamber is accurately regulated by the fuel pump and regulating means heretofore described. At each revolution of the cam 234 the roller 228 is operated to elevatethe lifter 221 which in turn engages the contact piece 220 on the plunger 140 to thrust the pump plunger 140 upward. During this stroke of the plun er liquid fuel in the chamber 320 (Fig. 2) etween' the plunger 140 and discharge valve nipple is forced under high pressure through the discharge line 185 to the inlet passage of the injector, whence it flows through the passages in said injector and out throu h the nozfile. The amount of fuel thus in ected into the engine is controlled by the needle valve 201 which, at a predetermined point during the stroke of the pump plunger, is elevated by engagement of the contact arm 241 with the lifter rod 242 which transmits its pressure to the lever 253 to elevate the needle valve stem in the manner heretofore described. The instant of such actuation of the needle valve is determined by the pos1- tion .of the fulcrum 258 of said lever 253,

which position in turn depends on the speed of the engine by reason of the control of said .fulcrum from the governor mechanism heretofore described. The instant the needle valve 201' is opened further discharge of fuel throughthe injector device ceases because the needle valve is in the discharge line between the fuel pump and the injector, and the, instant the needle valve is opened the fuel being forced under pressure from the chamber 320 returns to the inlet chamber 112 of the fuel pump through the needle valve chamber 114 and the by-pass 210.

As the cam 234 continues its rotation the lifter 221 is lowered by the action of spring 217 and contact arm 241 is lowered to permit the lifter rod 242 to be lowered by spring 204 'as it closes needle valve 201.

As the plunger 140 is lowered its inlet valve 145 is lifted from its seat 146 and liquid fuel is forced into the chamber 320 from the passage 141. At the same time a suction is exerted on the fuel in the inlet chamber 112 so that fresh. fuel flows into the chamber 134 and through the passage 141. At the end of the down stroke of plunger 140 inertia aids the spring 147 in closing valve .145. During the up stroke or discharge stroke of the pump plunger said inlet valve 145-is held to its seat by the pressure in the chamber 320, while the discharge valve 161 is lifted from its seat by the pressure in said chamber 320. Owing-to the small size and character of this chamber 320, the plunger 140 operates with high efficiency in discharging the fuel therefrom. During the up-stroke or discharge stroke of the plunger pressure on the fuel in the inlet chamber 112 maintains the chamber 134 and the passage 14:1 in the plunger full of fuel. When fuel flows into i said chamber 112 from the tank or other source of fuel provided, the shock of the infiowing fuel is absorbed by the air cushion at the upper end of said chamber 112.

In starting the engine a blow torch or other suitable source of heat may be applied to a suitable hot spot such as a hot tube in the engine cylinder until the same is sufliciently heated to ignite the charge of fuel and air in the combustion chamber, and thereafter the engine continues to run upon the Diesel or semi-Diesel pi'inciple in the manner well understood in the art.

It will therefore be perceived that an oil engine, particularly an engine of the Diesel or semi-Diesel type, has been provided which is highly flexible .in service and which is capableof running efiiclently under a wide variety of loads and speeds. At'the same time the engine is capable-of ready control, and may respond promptly to the varying conditions of, load and speed.

without interference from the en no.

Again referring to the requirements of such an engine in oil field service, it is capable of operating with entire satisfaction and efficiency under the varying conditions of load and speed required by such service:-As the drill reaches the top of its stroke and begins to drop, the engine will speed up, but without running away because of the governor control, so that the drill may make its stigoke ing this period the regulating devices heretofore-described are operated to cut down the,

quantity of fuel supplied to the engine, but the diminution in the fuel discharged into the engine cylinder is not in proportion to the drop in-load so that the engine speeds up. \Vhen the drill reaches the bottom of its stroke and rebounds, the engine is running at the proper speed for promptly picking up the drill on its rebound, and although the p'ckingup of the drill-is an assumption of full load conditions, the regulating devices heretofore terns heretofdre in use which are complicated and bulky instructure and expensive to install and maintain. At the same time the fuel pumping and regulating mechanism is promptly responsive, with the desired degree of sensitiveness,-to meet the varying conditions of operation of the engine, so that prop erly regulated quantities of fuel are discharged into the engine cylinder at the proper time, while undue increases or decreases of speed are prevented by the controlling and governing devices heretofore described.

There have also been provided improved devices for adjusting the timing of the fuel injection, for throwlng the fuel pump into and out of operation, for preventing undesirable vibrations in the fuel regulating mechanism, and for regulating the quantity of fuel delivered to the engine, as well as improved means for pumping liquid fuel and for'in may be made in the details of construction,

arrangement and proportion of parts, andcertain features may be used without other features. While the invention has been particularly described in conjunction with engines operating on the Diesel or saml Diesel cyc'e, certain featuresrof the invention are aps plicable to oil engines of other types,.an d

certain features of the invention are appllcable to internal combustion engines which employ a spark plug or magneto for initiating combustion, or which utilize a gaseous or vaporized fuel in place of atomized fuel,

or which operate onother cycles than'heretofore referred to. Reference is therefore to be had to the claims hereto appended for a defi nition of the limits of the invention.

What is claimed is: 1. In an internal combustion engine includngan engine cylinder and an injection device for injecting liquid fuel thereinto, a pump'including a plunger for forcing fuel through said injection device, a by-pass for the fuel, a valve controlling said by -pass and adapted to be moved to open position only during the fuel forcing stroke of said plunger, and means for operating said by-pass valve including a lever cooperating with the stem of said by-pass valve, means for continuously maintainingsa id lever in pivotal contact with said stem, a fulcrum device for said lever, means responsive to the speed of the engine for variously positioning said fulcrum de vice, and means positively movable by the plunger of said pump during its forcing stroke only for moving said lever about said fulcrum and thereby actuating the valve stem through the pivotal contact therewith of said lever.

2. In an internal combustion engine in cluding an engine cylinder and an injection device for injecting liquid fuel thereinto, a pump including a plungerfor forcing fuel through said injection device, a by-pass for the'fuel, a va'xve controlling said by-passand adapted to be moved to open position only 1 during the fuel forcing stroke of said plunger, and means for operating said by-pass valve including a lever cooperating with the stem of said by-pass valve, means for continuously maintaining said leverin pivotal contact with said stem, a fulcrum device for said lever, means responsive to the speed of the engine for variously positioning said fulcrum dc vice, means positively movable by the plunger of said pump duringits forcing stroke only for moving said lever about said fulcrum and thereby actuating the valve stem through the pivotal contact therewith of said lever, and means for preventing movement of said fulcrum device due to the movement of said lever when operated by said last-named means.

7 3. Inan internal combustion engine including an enginecylinder and an injection device for injecting liquid fuel thereinto, a pumpincluding a plunger for forcing fuel through said injection device, a by-pass for tl1e.fuel,a valve controlling said by-pass and adapted to be moved to open position-only during the fuel forcing stroke of said plunger, and means for operating said by-pass valve including a lever cooperatin withthe stem of said by-pass valve, means or continuous maintaining said lever in pivotal contact with said stem, a fp'lcrum device for said lever,

means respons ve to the speed of the engine for variously positioning said fulcrum de-' "ice, means positively movable by the plunger of said pump during its forcing stroke only for moving said lever about said fulcrum and thereby actuating the valve stem through the pivotal contact therewith of said vlever, and a. dash-pot connected to said fulcrum device for preventing movement thereof when said lever is operated by said last-named means.

4. In an internal combustion engine including an engine cylinder and an injection device for injecting liquid fuel thereinto, a

pump for supplying said injection devicewith fuel including a plunger, a by-pass for the fuel, a valve for said by-pass, a member pivotally contacting with the stem of said ting engagement with said member and a member movable with the plunger of said pump and mechanically disconnected from said rod for engaging and moving said rod during portions of the movement of said plunger.

5. In an internal combustion engine including an engine cylinder and an injection device for injectingliquid fuel thereinto, a pump for supplying saidinjection device with fuel including a plunger, a by-pass for the fuel, a

valve for said by-pass, a member pivotally connected with said by-pass valve, means responsive to the speed of the engine for variously positioning said member about its pivot, and means for operating said member ineluding a member movable with the plunger of said pump, a rod in the path of movement of said member, and a spring for holding said rod in engagement with said first-named member whereby said first-named member in its different positions of adjustment variously positions said rod for engagement at different times by said last-named member.

6. In an internal combustion engine including an engine cylinder and an injection device for injecting liquid fuel thereinto, .apump for supplying said injection device with fuel, I

said pump including a cylinder, a plunger in said cylinder, an inlet valve, said valve and the fuel conduit leading away therefrom being coaxial with said cylinder and plunger, a compression spring cooperating with said inlet valve, said spring being coaxial with and of larger diameter than said fuel conduit, a

spring retainin member provided with a passage to permit the fuel to flow around the spring and into said conduit when the spring is. compressed, and an outlet valve.

7. In an internalcombustion engine includ- .m'g

an engine cylinder and an injection device for injectingliquid fuel thereinto, a pump for supplying said injection device with fuel, said pump including a cylinder, a plunger in said cylinder, an inlet valve, an outlet valve, said outlet valve and the fuel conduit leading away therefrom being coaxial with said cy linder and plunger, a compression spring cooperating with said outlet valve, l

than said fuel conduit, and a spring retaining-member provided with a passage to permit the fuel to flow aroundthe spring and said spring. being coaxial with and of larger diameter ing an engine cylinder and an injection device ,for injecting liquid fuel theremto, a pump including a plunger for forcing fuel through said injection device, a by-pass for the fuel, a

spring-closed valve controlling said bypass and adapted to be moved to open position only during the fuel forcing stroke aid plunger, and means for opera-ting said by-pass valve including a lever cooperatin with the stem of said by-pass valve, means or continuouslyl maintaining said lever in pivotal contact wit said stem, a fulcrum device for said lever, means responsive to the speed of the engine for variously positioning said fulcrum-device, means posltively movable by the lunger of said pump during its forcing stro e only I for moving said lever about said fulcrum and 4 thereby actuatin the valve stem through the pivotal-contact-t erewith of said lever, and a dash-pot connected to said fulcrum device, the resistive efl'ect of said dash-pot bein greater than-that of the spring associa with said valve whereby movement of the fulcrum device is prevented when the lever V is operated by saidlast-named means.

- In testimony whereof I have signed this specification.

" F MARTIN KAI-IR. 

